‘To win over the Bernie brigades, Clinton has to do better than invoke fear of whoever the Republican nominee is. She has to summon her own inner protester.’
Photograph: Craig Ruttle/AP

What does Bernie Sanders stand for? Beyond stirring speeches, a candidate must have a plan for policy implementation, a clear programme. But at a recent meeting with the editorial board of the New York Daily News Sanders could not put forth any coherent specifics on how he would go about breaking up the big banks – one of the demands he’s most associated with in the public consciousness. He wasn’t sure whether the Fed had the power do it or Congress, where the legal authority resided. He was shaky on Israel-Palestinian relations. He was fuzzy on a lot else. Then he absurdly called Hillary Clinton “unqualified” to be president.

The Sanders campaign soon realised its mistake. On Friday morning the candidate was busy in television interviews explaining the precise section of the Dodd-Frank legislation that would apply. But this was too little, too late.

The revolution may be as impractical and unachievable as Trump’s promise to Make America Great Again

Not that the fuzziness mattered to Sanders supporters. His devoted following, mostly white and young, will remain steadfast to the end. Their loyalty to him is reminiscent of the Donald Trump supporters who don’t seem to care whether anything that comes out of his mouth is based on fact.

This is because both of their campaigns are rooted in the narrative of protest. Sanders has erected a big social justice tent that can fit in just about everyone on the left who responds to a call for revolution. But the Daily News session revealed that the revolution may be as impractical and unachievable as Trump’s promise to Make America Great Again.

A few nights afterwards, at the Flash Factory, a hip club in downtown Manhattan, the nitty-gritty of implementation didn’t seem to be on people’s minds. The venue was jammed with artists and activists for Sanders. What’s striking about Sanders’ supporters is how they’ve flocked to his campaign from so many different protest movements. Rebecca Goyette, and artist and educator, is typical. She’s been involved with Occupy Wall Street, Black Lives Matter and she once toured the US dressed as a missile to protest against the wars of the Bush administration. “Bernie is taking all these movements and ideas and putting them together in one platform,” she said. There are “fractivists” who helped ban fracking in New York, members of Greenpeace and many other causes.

When Sanders talks about economic inequality and the 1%, the rallying cry of Occupy, he uses morally charged terms to describe them. This language is central to his appeal. In 2014, I interviewed a group of Occupy protesters at an encampment they had erected near the World Economic Forum in Davos, Switzerland, ground zero of the global elite. Sitting in a yurt they had built (they had also made seven igloos) one of the protesters repeatedly used the word “immoral” to describe the power gathering.

When I first saw Zuccotti Park in 2011, I was surprised by how much smaller it was compared with what I’d seen on television. The Occupy protesters had a library and a kitchen, but no apparent leader. Now there’s Bernie. “Bernie is both a conduit and a tactic,” explained Winnie Wong, who helped create the Feel the Bern hashtag. Wong was in Zuccotti Park the first day of the Occupy protests and the last, when everyone was evicted. Then, not wanting Hillary Clinton to go unchallenged, she helped organize a campaign to draft Senator Elizabeth Warren of Massachusetts to run for the Democratic nomination. After that she immersed herself in the Sanders campaign. Another Occupy veteran, Raviv Ullman, thinks that even if Sanders loses the big state primaries coming up, New York, Pennsylvania and California, the Vermont senator has already succeeded in pushing Clinton to the left.

What’s interesting is that electing Sanders is not necessarily the end point for many of these activists. At each stop along the way to the Sanders campaign, they have gained sophistication in almost every area of politics, especially new organizing and fundraising techniques. While Occupy Wall Street seems to be the strongest thread tying them together, some cut their teeth on President Obama’s two campaigns.

“These people are really smart,” said Wong. And effective, at least in the most recent caucuses and primaries. They helped raise an astonishing $44m in March, part of a $183m haul since January 2015, mostly raised online with, as Sanders delights in saying, an average of $27. Clinton has displayed strength, especially in the black community and some of her close advisers have worked for insurgent Democratic presidential candidates since the late 1960s. But even with her perfectly fine environmental proposals and her more specific plan to tighten the screws on big banks, she cannot shake the image of being the candidate of the status quo. It’s patently clear that all her government service makes her better qualified to be president, but that’s her problem, too. She’s going to have to work hard to convert the Sanders activists to her side.

Some of the folks at the Flash Factory and others I interviewed said that if Clinton wins the nomination, they might vote the Green Party line. In a close general election, no Democrat wants to see another Ralph Nader spoiler. She didn’t help herself by getting angry at a Greenpeace worker and accusing the Sanders campaign of lying about her record. A video of the encounter went viral. Some saw her comment the morning after the election that “it’s exciting to be, in effect, protesting” as patronizing.

Like it or not, however, she will almost certainly be the left-of-centre candidate for president of the United States. It would serve all progressives – and that includes Sanders’ foot soldiers – if she were able to absorb some of the passion and protest of her opponents’ campaign and direct it towards a resounding Democratic victory. How can she do it? As EM Forster wrote: “Only connect.”

To win over the Bernie brigades, Clinton has to do better than invoke fear of whoever the Republican nominee is. She has to inspire. She has to summon her own inner protester. The one who gave the fiery commencement speech at Wellesley, the one who was late getting back to Yale Law School because she was too busy organizing Texas for George McGovern, the anti-war Democrat, in 1972. The one who angered Arkansas by keeping her own name after she married Bill Clinton. The lifelong feminist who’s been steadfast for abortion rights. She’s in there somewhere.